87121428 has 12 divisors (see below), whose sum is σ = 203283360. Its totient is φ = 29040472.

The previous prime is 87121387. The next prime is 87121429. The reversal of 87121428 is 82412178.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87121429) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3630048 + ... + 3630071.

It is an arithmetic number, because the mean of its divisors is an integer number (16940280).

Almost surely, 2^87121428 is an apocalyptic number.

It is an amenable number.

87121428 is an abundant number, since it is smaller than the sum of its proper divisors (116161932).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

87121428 is a wasteful number, since it uses less digits than its factorization.

87121428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7260126 (or 7260124 counting only the distinct ones).

The product of its digits is 7168, while the sum is 33.

The square root of 87121428 is about 9333.8860074462. The cubic root of 87121428 is about 443.3108170046.

The spelling of 87121428 in words is "eighty-seven million, one hundred twenty-one thousand, four hundred twenty-eight".